This paper used the Uganda National Household Survey (UNHS) dataset of 2005/06 to examine the productivity of improved inputs used by smallholder maize farmers in Uganda. Yield and gross profit functions were estimated with the stochastic frontier model. Results revealed a significant effect improved inputs use on yield but not gross profit. Moreover, farmers who planted recycled seed (of improved variety) without fertiliser obtained lower yield but the highest gross profit. Furthermore, if the opportunity cost of own land and labour inputs in maize production were imputed, overall, farmers made economic losses. Based on the prevailing farmers’ production technology and market conditions, maize cultivation in the range of 2-3 ha was found to give optimum profit while cultivation under 1 ha or above 4 ha led to economic losses. A major contribution of this paper is that maize cultivation in Uganda in 2005/06 and even at present was/may be of no economic consequence other than food, at household level.